Conveying jack



A. L. KERN March 28, 1933.

CONVEYING JACK Filed 001;. 13. 1931 INVENTOR {m Patented Mar. 28, 1933 UNITED STATES ALBERT I1. KERN, F JACKSON, .llLHGHIG'AN CONVEYING .mcx

Application filed October 13,1931. Serial No. 568,549.

My invention relates to a conveying jack and important objects thereof are to provide a jack of the character described, which will enable one person to easily convey or transport heavy crates, boxes and other heavy loads of any shape or size that rest flatly upon a floor, which may be readily installed in position to the load to be conveyed or removed therefrom, and which embodies novel 0 means for automatically locking the device in the operative position.

Further objects of the invention are to provide a device of the class stated, which is simple in its construction and arrangement, strong, durable and efi'icient in its use, compact, attractive in appearance, positive in its action, and comparatively inexpensive to manufacture.

With the foregoing and other objects in view which will appear as the description proceeds, the invention resides in the combination and arrangement of parts and in the details of construction hereinafter described and claimed, it being understood that changes in the precise embodiment of the invention hereinafter disclosed can be made within the scope ofwhat is claimed without departing from the spirit of the invention.

In the drawing wherein like numerals of references designate corresponding parts throughout the several views Figure 1 is a front view of a conveying j aok constructed in accordance with the invention.

Figure 2 is a side vlew thereof.

Figure 3 is a front view of the locking bar.

Referring in detail to the drawing 1 denotes a flat, vertically disposed supporting plate preferably provided with a relatively narrow upper portion 2. The n per end of the supporting plate 1 is curle forwardly providing a handhold 3 to facilitate the handling, transportation, and positioning of the device. The upper portion 2 of the supporting plate 1 is further formed with an aperture at to permit the suspension of the device when not in use.

The lower end of the supporting plate 1 is provided with a horizontally disposed load engaging flange 5. The engaging flange 5 extends rearwardly and is adapted for engag ng the edge margin of the under or bottom side of the load to be conveyed. The engaging flange 5 is preferably provided with a plurality ofupwardly disposed teeth '55 6, winch bite into the bottom side of the load and thereby maintain the latter in position upon the engaging flange 5.

A wheel 7 is revolubly mounted at the front of the supporting plate 1 between a pair of similar hearing arms, respectively indicated at 8 and 9, by means of a bearing bolt 10. The latter also extends through and is vertically shiftable in an oblong slot 11, which is formed in and extends along the vertical center of the supporting plate 1 ad acent to the lower end of the latter.

The converging upper ends of the bearing arms 8 and 9 are pivotally connected on respective sides of the lower endof a conmeeting arm 12, by means of a pivoting bolt 13, which provides a toggle joint connection between the pair of bearing arms 8 and 9 and the connecting arm 12.

The upper end of the connecting arm 12 1s plvotally connected to the supporting plate 1, by means of a pivoting bolt 14. The latter is mounted in the vertical center of the supporting plate 1 and disposed a considerable distance above the oblong slot 11 in which the bearing bolt 10 is engaged.

Vhen in the retracting position the pair of bearing arms 8 and 9 and the connecting arm 1:2 are disposed at an angle with respect to the vertical center of the supporting plate 1, whereby the wheel 7 is drawn upwardly to its retracted position above the load engaging flange 5, as clearly illustrated in Figure 1. hen the pair of bearing arms 8 and 9 and the connecting arm 12 are shifted to more nearly assume their vertical alignment, the wheel 7 is lowered to project a portion thereof below the load engaging flange 5, as shown in Figure2 and in dot and dash lines in F igure 1. 9

When the pair of bearing arms 8 and 9 and the associated connecting arm 12 are in the retracting position the knee 15 of their tog le joint connection is disposed at a considerafile distance from the vertical center at one side of the supporting plate 1. When the pair of bearing arms 8 and 9 and the connecting arm 12 are in the projecting position, the knee 15 of their toggle joint connection is disposed slightly beyond the other side of the vertical center of the supporting plate 1, and abuts against a stop pin 16, which is fixed in the supporting plate 1 and whereby the movement of the pair of bearing arms 8 and 9 and of the connecting arm 12 is limited when shifting to their projecting position.

The purpose of disposing the knee 15 of the toggle joint connection of the arms 8, 9 and 12, slightly beyond the vertical center of the supporting plate 1 when in their projecting position is to prevent the liability of said arms 8, 9 and 12 from accidentally shifting to their retracting position while a load is being carried by the device.

The bearing arm 8 carries a fixed cylindrical socket member 17, which extends parallel to the former and is adapted for engaging an end of an operating lever 18. The latter is removably engaged in the socket member 17 and is provided with an angularly disposed pinch bar end 19 for the purpose to be described. The function of the operating lever 18 is apparent for facilitating to shifting of the arms 8, 9 and 12 to their projecting and retracting positions.

\Vhile not absolutely essential to the suc cessful operation of my improved conveying jack, a locking bar 20 is preferably provided for securing the arms 8, 9 and 12 in their projecting positions. The locking bar 20 extends approximately horizontal and is pivotally connected, adjacent to one end thereof, to the supporting plate 1 by a pin 21. The other end of the locking bar 20 is provided with a horizontally extending slot 22, which is formed with an upwardly disposed notch 23 at the inner end thereof.

The slotted end of the locking bar 20 is disposed rearwardly of the connecting arm 12, and the latter carries a locking pin 24: which engages in the slot 22. hen the connecting arm 12 is shifting to the projecting position the locking pin 24 will travel along in the slot 22 until it reaches the inner end of the latter al owing the slotted end of the locking bar 20 to drop by gravity whereby the notch 23 will engage the locking pin 24 and secure the connecting arm 12 in the projecting position.

A releasing lug 25 is provided at the pivoted end of the locking bar 20 and projects beyond the adjacent side edge of the supporting plate 1. By depressing the lug 25, preferably with the foot, the slotted end of the locking bar 20 is elevated to disengage the notch 23 from the locking pin 24, thereby permitting the connecting arm 12 to be shifted to its angularly disposed retracting position.

The upper end of the connecting arm 12 is preferably provided with a laterally extending projection 26, which is disposed directly above the locking bar 20. A spiral spring 27 has one end thereof connected to the free end of the projection 26 by a pin 28. The other end of the spring 27 is connected to the locking bar pivoting pin 21.

The normal action of the spring 27 tends to shift the arms 8, 9 and 12 to the retracting position, and to maintain the latter in such position. hen the arms 8, 9 and 12 are in their projecting positions, the spring 27 is tensioned and will function to return said arms 8, 9 and 12 to their retracting positions as soon as the locking bar 20 is operated to release the locking pin 24 from the notch 23, in the manner herein set forth In practice the operation of my improved conveying jack is as follows :Assuming that it is desired to convey a heavy crate which rests flatly upon the floor, the operator first employs the pinch bar end 19 of the operating lever 18 to raise one side of the crate suiticiently to allow the engaging flange 5 of the supporting plate 1 to be inserted under the bottom of the raised side of the crate. Upon removing the operating lever 18 the crate will rest upon the flange 5 and will be maintained thereon by the engagement of the teeth 6 in the bottom of the crate. The opposed side of the crate is now raised by the operator and the flange 5 of a second conveying ack is inserted thereunder in a manner identical to that above described.

Of-course,itiisevidentthatwhiletheflanges 5 0f the ack are being inserted under the crate, in the manner stated, the wheels 7 are in their retracted positions above the flanges of the respective jacks. The operator now inserts the operating lever 18 into the socket members 17 of the jacks and shifts the arms 8, 9 and 12 to the projecting position, whereby a portion of the wheels 7 of the acks will be projected below the flanges 5 and the load of the crate will be carried by the wheels 7. By properly positioning the two conveying jacks employed to suitably balance the load, the operator may grasp the crate at any advantageous point and readily push or pull the same to any location desired.

It will be noted that when the load is resting upon the flanges 5 in the manner described, the upper end of the supporting plate 1 is forcibly drawn toward and against the side of the crate, whereby the conveying jacks are securely held in their relative positions while carrying the load of the crate.

To remove the conveying jacks from the crate it is only necessary to shift the wheel 7 thereof to their retracted positions, and to employ the operating lever 18 to slightly raise the crate to allow the withdrawal of the flanges 5 from under the latter.

From the foregoing description, it will be noted that at least two of my improved conveyin jacks are always employed and positione on opposed sides of the load to be conveyed. In practice, it may be found to be of advantage to use even more than two conveying jacks to facilitate the transportation of the load.

The present invention provides a most efficient device of its kind which may be successfully employed for facilitating the conveyance of heavy boxes, crates and analogous objects, particularly when the latter rest flatly upon a floor, and which in many instances obviates the necessity of truck and crane mechanisms now commonly employed for transporting heavy boxes and crates in stores, warehouses and the like.

What I claim is:

1. A load conveying jack comprising a supporting member provided with an oblong slot, a load engaging element carried at the lower end of said supporting member, a pair of bearing arms, a wheel mounted between said bearing arms, a bearing bolt pivotally connecting said wheel to the lower end of said pair of bearing arms and shiftably engaging in said slot, a connecting arm having its upper end pivotally connected to said supporting member, the lower end of said connecting arm having a toggle joint connection with the upper ends of said pair of bearing arms, said pair of bearing arms and said connecting arm being operable for projecting a portion of said wheel below said load engaging element and for releasing said wheel above the latter, and means for limiting the movements of said bearing and connecting arms when shifting to their projecting positions.

2. A load conveying jack comprising a supporting member provided with an oblong slot, a load engaging element carried at the lower end of said supporting member, a pair of bearing arms, a wheel mounted between said bearing arms, a bearing bolt pivotally connecting said wheel to the lower end of said pair of bearing arms and shiftably engaging in said slot, a connecting arm having its upper end pivotally connected to said supporting member, the lower end of said connecting arm having a toggle joint connection with the upper ends of said pair of bearing arms, said pair of bearing arms and said connecting arm being operable for projecting a portion of said wheel below said load engaging element and for releasing said wheel above the latter, means for limiting the movements of said bearing and connecting arms when shifting to their projecting positions, and means for automatically returning and maintaining said bearing and connecting arms in their retracting positions.

In testimony whereof I aflix my signature.

ALBERT L. KERN, 

